AUTOCLAVE WITH CONVEYOR FOR LOADING THE SAME

Description

[0001] The invention relates to an autoclave for the pressure and / or temperature treatment of products, in particular for preserving food. The autoclave comprises a pressure vessel defining a pressure chamber for receiving the products. Preferably, the autoclave also comprises a rotating device for rotating the products introduced into the pressure chamber during treatment, comprising at least one rotating frame arranged within the pressure chamber for receiving the products, a rotary drive arranged outside the pressure chamber, and a drive shaft extending between the rotating frame and the rotary drive through a pressure- and / or temperature-safe opening in the pressure vessel.

[0002] Such autoclaves are primarily used for preserving products such as food. The food is typically packaged in containers such as jars, cans, or similar containers. For treatment in the autoclave, the products are typically arranged in so-called product cages, which are moved into the autoclave and removed again after the preservation treatment is complete. Within the product cages, the products are stacked on top of each other using perforated intermediate layers. The product cages and intermediate layers are designed to be permeable to water or steam to ensure uniform water / steam treatment of all products in the autoclave.

[0003] The pressure vessel of the autoclave is usually cylindrical and is generally arranged horizontally. To load such an autoclave, one product cage after the other is moved into the pressure vessel along the longitudinal axis of the cylindrical pressure vessel with the pressure-tight lid of the autoclave open. Roller conveyors or similar devices running parallel to the longitudinal axis of the pressure vessel can be provided for this purpose. The product cages are placed onto these conveyors and can be rolled from the autoclave inlet deeper into the autoclave. Such loading has so far mostly been done manually, with the product cages being pushed individually on trolleys in front of the autoclave, the trolley being locked to the floor, and then the product cage being pushed onto the roller conveyors of the autoclave using long rods.Product cages are gradually inserted into the autoclave, with previously inserted product cages being pushed further into the autoclave using considerable force. After the heat or pressure treatment in the autoclave, the product cages must be removed manually.

[0004] The current method of loading the autoclave is therefore disadvantageous for ergonomic reasons alone. When pushing the product cages into the rear part of the autoclave, large masses – a single product cage can weigh 300 kg or even 400 kg, for example – have to be moved in a bent position using muscle power. Despite the passive roller conveyors, which facilitate pushing in, this results in a high labor and time expenditure. For example, with an autoclave containing four product cages and an assumed process time of one hour, 32 product cages are moved in and out per work shift and autoclave. Each worker typically loads and unloads at least four autoclaves. This results in 128 product cages being moved in and out of the autoclave per shift and worker.

[0005] A particular difficulty arises from the rotation of the products within an autoclave comprising a rotating device during treatment. The product cages are held within the rotating frame and, during pressure or temperature treatment in the autoclave, are usually rotated or pivoted relative to the pressure vessel around the longitudinal axis of the pressure vessel. Such rotation enables better heat distribution through mixing within the product and thus better heat transfer to the products. For this purpose, the product cages are fixed in the rotating frame during the process. They are driven by the rotary drive located outside the pressure vessel, which is connected to the rotating frame via a shaft sealed from the pressure vessel. Integrating a conveyor system for feeding the autoclave is a major challenge, particularly in autoclaves with a rotating device.

[0006] US 2018 / 0070615 A1 describes a device for use in conjunction with autoclaves for sterilization, and in particular, a system and method for automatically loading and unloading autoclaves. The system comprises rigid chain units aligned with an access opening of the autoclave such that a rigid chain can be conveyed along a chain conveyor path through the access opening into the autoclave.

[0007] US 2006 / 0130667 A1 describes a clamping device for use in an autoclave and a system for securely securing a basket or a series of baskets containing a product within an autoclave. The preferred embodiment is used with rotary autoclaves, which include a rotating insert for receiving product-loaded baskets. A bellows system is used to securely position and support the baskets within the autoclave, with the baskets being clamped to the rotating insert during the autoclaving process.

[0008] WO 2008 / 093367 A1 relates to a system for pasteurising food which is intended to achieve better performance than existing systems.

[0009] EP 2 377 560 A1 relates to rotating, discontinuous autoclaves of the horizontal end-over-end type with counterpressure sterilization technology. This technology is designed to neutralize the effects of the overpressure that inevitably builds up inside the containers during sterilization with flows in the same direction. The autoclave utilizes both stationary nozzles located in the upper part of the sterilization chamber and movable nozzles that rotate with baskets. The baskets are loaded with containers containing the product.

[0010] The invention is based on the object of providing an autoclave, in particular an autoclave with a rotating device, which can be loaded with products in an ergonomically favorable and efficient manner.

[0011] The invention solves the problem by an autoclave according to claim 1. Advantageous embodiments are the subject of the dependent claims, the description and the figures.

[0012] According to the invention, the autoclave of the type mentioned at the outset comprises a conveyor device for feeding the autoclave, wherein this conveyor device comprises the following: conveyor means arranged within the pressure chamber for transporting the products from an inlet of the autoclave deeper into the autoclave, as well as a conveyor drive arranged within the pressure chamber for driving the conveyor means. As will be explained later, the conveyor drive is preferably a fluid-powered drive that is supplied via fluid lines. In addition, according to the invention, the autoclave has the rotating device mentioned at the outset, wherein the conveyor means and the conveyor drive can be rotatable together with the rotating frame and wherein the fluid lines extend through the

[0013] can extend through the drive shaft to the outside of the pressure vessel and can be connected there to a fluid power supply unit via a fluid power rotary union.

[0014] The autoclave according to the invention is used in particular for the temperature treatment of products, either at elevated pressure or without pressure. Such products include, in particular, foodstuffs, which are sterilized or preserved in the autoclave. However, building materials such as sand-lime bricks can also be treated, in particular cured, in the autoclave. As a further example, fiber composite components made of fiber-reinforced plastics can be treated as products. Vulcanization of rubber parts can also take place as products. The products, in particular foodstuffs, are introduced into the pressure chamber of the autoclave, in particular in product cages. Thus, in particular, foodstuffs can be introduced into the rotary frame of the autoclave provided according to the invention in product cages as mentioned above. The product cages are fixed to the rotary frame. A clamping device for fixing the product cages can be provided in the rotary frame.During the treatment process, the rotary drive can then rotate the drive shaft and thus the rotary frame together with the products accommodated therein in the well-known manner. Rotation does not necessarily mean a rotation of 360°. Rather, at least in some processes, the drive shaft can be rotated to one or both sides by a smaller angular range. The product cages can thus be pivoted to one or both sides. This allows even heating of the products. The autoclave can incorporate a heat source for heating, in particular a hot gas source or a microwave source. In the food industry, i.e. for heating food, steam is usually used.

[0015] Thanks to the conveying device according to the invention, the autoclave can be loaded and unloaded easily, supported by a drive. Manual loading / unloading is therefore no longer necessary. For this purpose, the product cages can still be moved towards the autoclave by hand, whereby the transfer of the product cages to the conveying means within the pressure chamber can also be achieved manually as before. The conveyor drive then conveys the product cages deeper into the autoclave using the conveyor means without the use of muscle power. For this purpose, the conveyor means can extend from the inlet of the autoclave deep into the autoclave, in particular to one end of the autoclave, such that the autoclave can be completely loaded using the conveyor means. The conveyor drive can be started manually or start automatically upon contact with a product or product cage.

[0016] According to the invention, the conveyor drive – like the conveying means – is arranged within the pressure chamber. This arrangement is particularly advantageous because the drive can act directly on the conveying means. The conveyor drive is designed in such a way that it can withstand the environmental influences in the autoclave during operation, i.e. in particular the high pressures and / or temperatures that occur during operation. The conveyor drive can thus remain within the pressure chamber during operation of the autoclave, i.e. during the process. Supply lines can be provided to supply the conveyor drive, which lead out of the pressure chamber. These supply lines can lead, in particular, via a pressure- and / or temperature-safe feedthrough from the pressure chamber to the environment of the pressure vessel. This makes it possible to supply the conveyor drive even during operation of the autoclave.

[0017] While an electric drive is conceivable as a conveyor drive, it is not preferred because it would require considerable effort to make it resistant to the ambient conditions (temperature and pressure) prevailing during autoclave operation. There is always a risk that process water could penetrate the electric drive during autoclave operation.

[0018] Preferably, therefore, a fluid power conveyor drive is provided which is supplied via fluid lines as supply lines. Such a drive can withstand the ambient conditions prevailing during operation of the autoclave. In particular, a pressure in the drive and the fluid lines can be maintained even during operation of the autoclave. The fluid lines can lead from the pressure chamber to the environment of the pressure vessel via a pressure- and / or temperature-safe feedthrough. Fluid power means that the energy or force is transmitted by a flow of gases or liquids. The conveyor drive can be a pneumatic drive or a hydraulic drive, for example. Such a drive is resistant to the ambient conditions prevailing in the autoclave during the process, in particular pressure and temperature, particularly due to the lack of electrical components.The conveyor drive can therefore remain inside the autoclave during the process without damage. The same applies to the conveying means, which can be, for example, conveyor chains. Furthermore, according to the invention, both the conveying means and the conveyor drive are rotatable together with the bogie, in particular, they are accommodated in the bogie. The fluid lines are also preferably rotatable together with the bogie, at least with their line sections located within the pressure chamber.

[0019] A particular challenge is supplying the conveyor drive with fluid from outside the autoclave via the aforementioned feedthrough from the pressure chamber to the surroundings of the pressure vessel. This was solved for an autoclave with a rotary drive by extending the fluid lines outward through the existing drive shaft of the rotary drive that rotates the bogie. Thus, the fluid lines for supplying the fluid-powered conveyor drive preferably extend through the drive shaft of the preferably provided rotary device to the outside of the pressure vessel, where they are connected to a fluid-powered supply unit via a fluid-powered rotary feedthrough. For this purpose, longitudinal bores can be used, for example, through the drive shaft.A fluid power rotary union is then provided outside the pressure vessel, which ensures the transition to the stationary fluid power supply unit in a manner known per se.

[0020] The conveying device described is particularly suitable for the rotation process, as no mechanical power flow with a stationary drive is necessary. According to the invention, the autoclave therefore has a rotating device for rotating the products introduced into the pressure chamber during treatment, with at least one rotating frame arranged inside the pressure chamber for receiving the products, a rotary drive arranged outside the pressure chamber and a drive shaft running between the rotary frame and the rotary drive through a pressure and / or temperature-safe opening in the pressure vessel, wherein the conveying means and the conveying drive are rotatable together with the rotating frame. Thus, with the fluid power conveying device described, in which the conveying means, conveying drive and the components located inside the pressure chamber or...Since the fluid lines located on the drive shaft rotate with the rotating frame, and a fluid connection to the outside is achieved via the drive shaft of the rotating device, easy loading is also possible for autoclaves with a rotation process / rotating device. However, the conveyor drive is also useful for autoclaves without a rotating device, especially since no shaft seal is required.

[0021] In particular, the fluid supply to the conveyor drive of the conveyor system, which is arranged within the pressure chamber, can be maintained during the process, i.e. during the treatment of the products in the autoclave under high pressure or high temperature. In this way, an excess pressure can be maintained within the components of the conveyor system, in particular within the conveyor drive, compared to the conditions prevailing in the pressure chamber during the process. This prevents contaminants, in particular process water, from penetrating the conveyor drive during the process, which could otherwise impair its functionality. In other words, the joint pressurization of all supply lines during the process can prevent process water from penetrating the supply system. It is therefore preferable not to disconnect the energy supply from the conveyor drive during the process.However, the drive itself is preferably inactive during the process, since conveying the products via the conveyor means is not desired at this time.

[0022] In summary, according to a preferred embodiment, the autoclave has the following features: a pressure vessel defining a pressure chamber for receiving the products, a rotating device for rotating the products introduced into the pressure chamber during treatment, with at least one rotating frame arranged within the pressure chamber for receiving the products, a rotary drive arranged outside the pressure chamber, and a drive shaft extending between the rotary frame and the rotary drive through a pressure- and / or temperature-safe opening in the pressure vessel, a conveyor device for feeding the autoclave, with conveyor means arranged within the pressure chamber for transporting the products from an inlet of the autoclave deeper into the autoclave, a fluid-technical conveyor drive arranged within the pressure chamber for driving the conveyor means, and fluid lines supplying the conveyor drive,wherein the conveying means and the conveyor drive are rotatable together with the bogie and wherein the fluid lines extend through the drive shaft to the outside of the pressure vessel and are connected there via a fluid power rotary union to a fluid power supply unit.

[0023] According to one embodiment, roller conveyors are arranged within the pressure chamber, along which the products, in particular the product cages holding the products, can be conveyed by means of the conveying means. As already mentioned at the beginning, the products, in particular the product cages, can be pushed into the pressure vessel on such roller conveyors. Such roller conveyors are particularly advantageous in combination with the conveying device according to the invention. The conveying device can thus grip the products or product cages and convey them into the autoclave along the roller conveyors that may already be present. The conveying means can, for example, extend parallel to the roller conveyor, in particular underneath the product cages. The conveying means can, for example, interact with the products or product cages in a force-fitting manner, in particular by means of spring-loaded conveying means, or else in a form-fitting manner.A positive locking mechanism can be achieved using cams provided on the conveyors that engage or engage with the products or product cages. This allows them to be pulled along the roller conveyors.

[0024] According to one embodiment, one or more of the following are provided as conveying means: conveyor chains, conveyor belts, conveyor ropes. Conveyor chains, for example made of steel, can be particularly useful, as they are particularly resistant to the conditions prevailing during the process. The conveying device can thus be a chain conveyor. The conveyor chains can be pressed, in particular, force-fitting, preferably with an adjustable force, for example, from below, against the products / product cages, thus lifting them at least slightly. The conveying device can generally be designed such that conveying takes place exclusively via the conveyor means.

[0025] However, as already mentioned, conveying can also be carried out in combination with a roller conveyor if provided.

[0026] According to one embodiment, the conveyors are spring-mounted. In particular, a chain conveyor as described above can be spring-mounted. This type of spring allows the conveyors to yield when picking up the products or product cages, reducing the risk of damage or overloading the conveyors.

[0027] According to one embodiment, the sections of the fluid lines running through the drive shaft are formed as longitudinal bores in the drive shaft. The fluid lines can be routed along these longitudinal bores. However, these bores themselves can also form the fluid lines within the drive shaft. In this case, separate fluid lines do not need to be introduced into the drive shaft, but rather only longitudinal bores, which can then serve as fluid lines. This is particularly simple.

[0028] According to one embodiment, a pneumatic conveyor drive is provided as the conveyor drive, wherein the fluid lines are pneumatic lines, the fluid power rotary union is a pneumatic rotary union, and the fluid power supply unit is a pneumatic supply unit. As already mentioned, however, instead of a pneumatic conveyor drive, a hydraulic conveyor drive can also be provided, with the other elements of the hydraulic conveyor device then being designed accordingly hydraulically. For example, a compressed air gear motor can be provided as the conveyor drive. Such a pneumatic conveyor device is particularly suitable for an autoclave with a rotation device. This allows the pressure within the pneumatic system to be maintained simply and reliably, so that no water penetrates the conveyor device during the process.In the event of damage to the pneumatic conveying device, for example due to wear and tear, only compressed air enters the autoclave, not hydraulic fluid.

[0029] Embodiments of the invention are explained below with reference to figures. They show: Fig. 1 shows an autoclave according to the invention in a perspective view, wherein the pressure vessel is shown transparent to illustrate the elements located therein and the closure lid is omitted, Fig. 2 shows the Figure 1 Fig. 3 shows a schematic side view of an autoclave according to the invention, and Fig. 4 shows a section of an autoclave according to the invention in the area of the drive shaft.

[0030] Unless otherwise stated, the same reference symbols refer to the same items.

[0031] In Figure 11 shows an autoclave 10 according to the invention, which comprises a horizontal, cylindrical pressure vessel 12. The pressure vessel 12 delimits a pressure chamber 14 in which four product cages 26 are accommodated. The autoclave 10 comprises a rotating device for rotating the product cages 26 accommodated in the pressure chamber 14. The rotating device comprises a rotary frame 16, also referred to as a rotating drum, with raceways or support rings 17, 17a running along an inner circumference of the pressure vessel 12 and clamping strips 20 extending parallel to the longitudinal axis of the pressure vessel 12 for clamping the product cages 26 within the rotary frame 16. The frontmost ring is referred to as the raceway 17, while the other three rings serve as support rings 17a for absorbing the clamping forces.Furthermore, the rotating device comprises a rotary drive 22 arranged outside the pressure chamber 14 and a drive shaft 24 running between the bogie 16 and the rotary drive 22, which is inserted into the . Figures 3 and 4 can be seen.

[0032] During the process, i.e. during the pressure or temperature treatment of products held in the product cages 26, the rotating frame 16 and thus the product cages 26 are rotated about the longitudinal axis A of the pressure vessel 12. This enables a uniform temperature introduction into the products held in the product cages 26, which can in particular be packaged food products. For such rotation of the rotating frame 16, the rotary drive 22 engages the drive shaft 24 and rotates it about the longitudinal axis A of the pressure vessel 12. The bearing ring 17 runs on support wheels 19, which are accommodated in wheel housings 18 in the wall of the pressure vessel 12. The product cages 26 are securely held in the rotating frame 16 via the clamping strips 20.

[0033] The autoclave 10 shown comprises a conveyor device 30 according to the invention for feeding the autoclave 10. This conveyor device 30 is in Figure 2in detail. In the present embodiment, the conveyor device 30 is designed as a chain conveyor, comprising a conveyor chain 32 as a conveying means, with which the product cages, which are manually moved to the autoclave, are Figure 2 visible inlet of the autoclave 10 to the opposite end of the autoclave. The chain conveyor 30 pulls the product cages 26 along non-driven roller conveyors 28, which also run parallel to the longitudinal axis of the pressure vessel 12. Within the pressure chamber 14, a pneumatic conveyor drive 34 is also arranged as part of the conveyor device, which drives the conveyor chain 32 via a drive chain 33. Further details are in Figure 3 to recognize.

[0034] Figure 3shows a schematic side view of the autoclave 10 looking through the pressure vessel 12. This view also shows the closure lid 13 of the autoclave 10, as well as a quick-release fastener 15 for securing the closure lid 13 in its closed position on the pressure vessel 12. Only two product cages 26 are shown in this illustration. As previously explained, the rotary frame 16 can be rotated via the external rotary drive 22, which rotates the drive shaft 24 and thus the rotary frame 16 connected to the drive shaft 24 about the longitudinal axis A of the pressure vessel 12. The rotary frame 16 is guided at one end within the pressure vessel 12 via a front bearing 21, which can in particular be the support wheels already mentioned, and at the other end via a rear bearing 25 between the drive shaft 24 and the pressure housing 12.

[0035] Also in Figure 3The conveyor chains 32 and the pneumatic conveyor drive 34 are visible in the inlet area of the autoclave. Internal fluid lines 36 extend from the conveyor drive 34 within the pressure chamber 14 to the other end of the pressure vessel 12, where they merge into longitudinal bores 37 of the drive shaft 24. During the process, the conveyor drive 34, the conveyor chain 32 and the fluid lines 36, 37 rotate together with the rotary frame 16 and the drive shaft 24 about the longitudinal axis A. A transition from the rotating fluid lines 36, 37 to stationary fluid lines 38 located outside the pressure vessel is achieved via a pneumatic rotary union 40. A fluid valve 42 ensures the connection to a pneumatic supply unit (not shown).

[0036] The passage between pressure chamber 14 and the environment of the autoclave is in Figure 4shown in detail. In particular, the drive shaft 24 is visible, as is a seal 23 for the drive shaft 24, which seals the pressure chamber 14 from the environment. Furthermore, the longitudinal bores 37 in the drive shaft 24, which form part of the fluid line, are visible. Also visible here are the channels of the pneumatic rotary union 40, which enables the transition between the lines 36, 37 rotating about the longitudinal axis A and the subsequent stationary lines 38. As explained, the entire drive shaft 24, including the fluid lines 37 running therein, as well as the bogie 16 and the fluid lines 36 running in the pressure chamber, rotate about the longitudinal axis A.

[0037] The conveying device according to the invention thus allows for simple and ergonomic loading even for an autoclave with a rotation process, i.e., a rotating device. The pneumatic conveying drive is resistant to the temperature and pressure conditions prevailing within the pressure chamber during the process. The same applies to the conveyor chain and the fluid lines. Advantageously, the supply to the conveying drive, i.e., in particular, the air pressure prevailing within the conveying device, can be maintained even during the process, with all supply lines being subjected to the same pressure. This prevents contaminants, especially water, from penetrating the conveying drive during the process. This could otherwise lead to damage or impairment of the conveyor drive.

[0038] Between individual treatment processes, the autoclave can be easily loaded via the conveyor system. For example, the product cages can be manually moved to the autoclave and placed on the roller conveyors 28 with the cover 13 open. The chain conveyor 30, which is particularly spring-mounted, can bring the conveyor chain 32 into frictional contact with the product cages 26. The conveyor drive 34 can then move the conveyor chain 32, allowing the product cages to be moved deep into the pressure vessel, sliding along the roller conveyors 28. List of reference symbols

[0039] 10Autoclave 12Pressure vessel 13Cover lid 14Pressure chamber 15Quick-release fastener 16Bogie 17Running rings 18Wheel housings 19Support wheels 20Clamping strips 21Front bearing 22Rotary drive 23Seal 24Drive shaft 25Rear bearing 26Product cages 28Roller conveyors 30Chain conveyor 32Conveyor chain 33Drive chain 34Pneumatic conveyor drive 36, 37Fluid lines 38Stationary fluid lines 40Pneumatic rotary union 42Fluid valve

Claims

1. An autoclave (10) for the pressure and / or temperature treatment of products, in particular for preserving food, comprising a pressure vessel (12) defining a pressure chamber (14) for receiving the products, characterized by a conveying apparatus for charging the autoclave (10), having - conveying means (32) arranged inside the pressure chamber (14) for transporting the products from an inlet of the autoclave (10) deeper into the autoclave (10), - a conveyor drive (34) arranged inside the pressure chamber (14) for driving the conveying means (32), and a rotary device for rotating the products introduced into the pressure chamber (14) during the treatment, having - at least one rotary frame (16) receiving the products and arranged inside the pressure chamber (14), - a rotary drive (22) arranged outside the pressure chamber (14), as well as - a drive shaft (24) running between the rotary frame (16) and the rotary drive (22) through a pressure and / or temperature-proof opening of the pressure vessel (12), - wherein the conveying means (32) and the conveyor drive (34) are rotatable together with the rotary frame (16).

2. The autoclave (10) according to claim 1, characterized in that the autoclave (10) has supply lines (36, 37), which lead out of the pressure chamber (14), for supplying the conveyor drive (34).

3. The autoclave (10) according to claim 2, characterized in that the supply lines (36, 37) for supplying the conveyor drive (34) extend through the drive shaft (24) to the outside of the pressure vessel (12).

4. The autoclave (10) according to one of the preceding claims, characterized in that the conveyor drive (34) is a fluid-operated conveyor drive (34) which is supplied via fluid lines (36, 37) as supply lines.

5. The autoclave (10) according to claim 3 and 4, characterized in that the fluid lines (36, 37) for supplying the fluid-operated conveyor drive (34) extend through the drive shaft (24) to the outside of the pressure vessel (12) and are connected there to a fluid-operated supply unit via a fluid-operated rotary feedthrough (40).

6. The autoclave (10) according to one of the preceding claims, characterized in that roller tracks (28) are arranged inside the pressure chamber (14), the products, in particular the product cages (26) receiving the products, being able to be conveyed along said roller tracks by means of the conveying means (32).

7. The autoclave (10) according to one of the preceding claims, characterized in that one or more of the following are provided as conveying means (32): conveyor chains, conveyor belts, hauling cables.

8. The autoclave (10) according to one of the preceding claims, characterized in that the conveying means (32) are spring-mounted.

9. The autoclave (10) according to claim 5, characterized in that the line sections of the fluid lines running through the drive shaft (24) are configured as longitudinal bores in the drive shaft (24).

10. The autoclave (10) according to claim 5, characterized in that a pneumatic conveyor drive is provided as the conveyor drive, wherein the fluid lines are pneumatic lines, the fluid-operated rotary feedthrough is a pneumatic rotary feedthrough and the fluid-operated supply unit is a pneumatic supply unit.